Remove xfail from test_os_exit_exits_within_timeout (#2737)

Removed xfail marker from test_os_exit_exits_within_timeout.

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Author: ognyanstoimenov

python/tests/stress/arcticdb/version_store/test_deallocation.py

@@ -41,7 +41,6 @@ def killed_worker(lib, io_threads, cpu_threads):
 
 @pytest.mark.parametrize("io_threads_spawned_in_child", [True, False])
 @pytest.mark.parametrize("cpu_threads_spawned_in_child", [True, False])
-@pytest.mark.xfail(reason="Intermittent failure 9917390284", strict=False)
 def test_os_exit_exits_within_timeout(
     lmdb_storage, lib_name, io_threads_spawned_in_child, cpu_threads_spawned_in_child
 ):